Variable flow rates for hybrid systems

[Kobus Jooste]

I have had this sitting in front of me for a long time, but only decided to put it into discussion format now.  There has been a fair amount of debate around oxygenation and flood and drain cycles of late.  Much of the discussion relates to how a system is operated - either timed, always on, fast cycling, periodic cycling, using wicking theory or flooding the whole bed.

 

In the hybrid zone, I believe that there is a need to understand that we can do multiple flow rates of one pump if we so desire.  The fact that my grow beds containing media are currently cycling fast have no bearing on my NFT or Raft tank flow rates, which are controlled by simple valves.  I do have a minimum flow rate in my media beds as a result of my siphon design, but I believe that if I change the stand pipe configuration I use to Affnan's design I would be able to slow the flood-and-drain cycle period in the beds further.  To take the thought pattern to a logical conclusion, I can follow up on the desire to add a small sump pump by having it as a timed unit.  This way, I'd be able to run an intermittantly cycling media bed in the set-up should I ever feel the need to.  I can also add dedicated cascade producing vessels such as siphoned header units and make all my media beds timed cycling set-ups if I want to.

 

My thoughts are therefore drifting towards having multiple growth environments as well as multiple flooding regimes in my single unit.  In theory, I can do this without an increase in current power consumption as my water pump is old generation (bloody thing won't pack up :)) and consumes 70 Watt to move just under three cubes of water per hour.  I can get a 45 Watt unit doing the same these days, thus with one of them and one slightly smaller unit, I can run split flow rates without feeling the pinch in the power bill. Two gravel sizes, four different growing environments and three flow rates in one unit.

[Harold Sukhbir]

So we have a mixed hybrid system with controller adjusting to a fixed regime( which he can also manipulate their function mainly through adjusting flow rate) and adding a second pump to intermittently change the original fixed regime.........or something to that effect. I am aware that anything we to to create increased water movement, especially in the system you've described, will lend to strengthen of our nitrifying colonies and by extension, up our outputs.I think that conventional rule of thumb AP puts a limit on a systems ability to produce nutrient, and since this is one of the main goals in AP design I'm all for increasing this potential. I don't consider that by adding aeration or increasing water movement, adding selective nutrient, changing fish feeds, or anything the controller does to maximize the potential of his AP system, he is moving away from conventional backyard AP.

[Kobus Jooste]

I'm not sure where "conventional" will be a few years on.  Right now, some AP models, if turned into cars, will only have reverse, second and fith, and may not start on Wednesday or Sunday.  I cannot understand why people will continue to use "either or" approaches in stead of an integrated one where you can cater for a wide range of plants and maximise your carrying capacity per unit area developed.  The more we move away from "salad greens" and into "total fresh food supply" desires, I think we will start seeing more and more hybrid approaches.  I am also over the one pump mantra.  If I use 70 Watts, I do not care if it is one or three really.  With more than one though, I can have a dedicated filtered, raw, timed and continuous flow supply.

Harold Sukhbir said:

So we have a mixed hybrid system with controller adjusting to a fixed regime( which he can also manipulate their function mainly through adjusting flow rate) and adding a second pump to intermittently change the original fixed regime.........or something to that effect. I am aware that anything we to to create increased water movement, especially in the system you've described, will lend to strengthen of our nitrifying colonies and by extension, up our outputs.I think that conventional rule of thumb AP puts a limit on a systems ability to produce nutrient, and since this is one of the main goals in AP design I'm all for increasing this potential. I don't consider that by adding aeration or increasing water movement, adding selective nutrient, changing fish feeds, or anything the controller does to maximize the potential of his AP system, he is moving away from conventional backyard AP.

[Harold Sukhbir]

Kobus said:"Right now, some AP models, if turned into cars, will only have reverse, second and fith, and may not start on Wednesday or Sunday."

Harold said:"HaHaHaHaHa!"

 

Kobus said:"The more we move away from "salad greens" and into "total fresh food supply" desires, I think we will start seeing more and more hybrid approaches."

Harold said:Totally agree. This i think is what will serve to push out and possibly over the "Box" in the way of design and other inputs.

[Kobus Jooste]

O dear, I may get zapped for that one but I think that the way aquaponics evolved, the technology platforms are typically too rigid for a diverse home production system.  Commercial units are all about best crops for the market and highest value crop, but home systems are not that one dimentional.  I have 25 different cultivars or species going right now, everything from cut flowers to water melon.  If I quickly add up all the different growing environments that would be best suited for my plants, there are 5 or 6, yet we only have systems typically capable of supplying 2 or 3 of these as mainstream home AP designs.

 

I'm a multi tool kind of person and want an all in one unit.  This may not make sense on a large scale, but I believe that if it can be made simple enough for home users, it should become popular.

Harold Sukhbir said:

Kobus said:"Right now, some AP models, if turned into cars, will only have reverse, second and fith, and may not start on Wednesday or Sunday."

Harold said:"HaHaHaHaHa!"

 

Kobus said:"The more we move away from "salad greens" and into "total fresh food supply" desires, I think we will start seeing more and more hybrid approaches."

Harold said:Totally agree. This i think is what will serve to push out and possibly over the "Box" in the way of design and other inputs.

[Harold Sukhbir]

To borrow from your reference, Ap is simply waste water treatment with an interesting side effect called "Vegetables". Trick is though, is how create a suitable environment for a variety of plants in one AP system?

[Kobus Jooste]

Multiple sources of water (but still only one fish tank) and more than one pump.  A line of unfiltered water for the gravel beds, a line of clean water for NFT / towers and flow control / timers to have either fast or slow cycling.  Sounds complex but I think I can do it in a 3 x 3 meter space.  Just need to wrap my head around the plumbing and the most effective way to hack into my current lay-out.  One pump always on and one on a timer should cut it.

[Harold Sukhbir]

When you figure out the logistics and implement, please show it to us!

[Kobus Jooste]

Will do, but it will have to wait until my next batch of funding is released :(